Preheat your oven to 350°F (175°C) and prepare a loaf pan by greasing it lightly.

Combine softened unsalted butter and canola oil with granulated sugar in a large mixing bowl and beat until light and fluffy.

Add the large eggs one at a time, mixing well after each addition, then pour in the vanilla extract and mix until smooth.

In a separate bowl, whisk together flour, baking powder, and salt, then gradually add to the wet ingredients along with the buttermilk.

In a small bowl, mix a portion of the batter with molasses and cinnamon until incorporated.

Pour half of the plain batter into the loaf pan, dollop half of the cinnamon mixture on top, then repeat the layers.

Gently swirl the batter with a knife to create a marbled effect.

Bake in the preheated oven for 40-45 minutes or until a toothpick comes out clean.

Allow the loaf to cool in the pan for 10 minutes before transferring to a wire rack.

While the loaf cools, mix melted butter with brown and granulated sugar, then brush the cooled bread with butter and roll it in the sugar mixture.

Slice and serve the bread warm.